Have all powder-coated sheets a PEI layer?
Hi,
Recently I ordered and got a powder-coated "Headbed Steel Sheet" in addition to the original smooth PEI "PA-11". Printing on the smooth PEI bed is working very well for more than a year.
The powder-coated sheet is slightly thinner than the flat sheet, so I did a first layer calibration before using it.
The texure is great but the parts do not stick to the bed as well as with the smooth PEI bed. Some of the parts even warp a bit (Prusa PLA, standard PrusaSlicer settings). The sheet certainly is powder-coated, but doesn't look very PEI-ish.
The bed has type "BH-25", so is different from the powdered sheet with PEI in the shop which is type "WA-15". (The type is not used in the text but in the top right of the sheet, see image).
The question is: has the "BH-25" the PEI layer?
Printer i3 MK3S (upgraded kit)
Greetings & thank you,
Fred Jan
RE: Have all powder-coated sheets a PEI layer?
I can't say for certain, but some of the discussions hint the material is Ultem. Ultem is a PEI material applied by spraying onto the steel instead of a sheet that is glued to the steel.
Prusa recommends not washing the PC sheets in soap and water due to fears of oxidation of the metal under the Ultem coating. Some users have reported the spattered coating breaks loose, small individual lumps come off with the part. But this seems to happen regardless of the washing method.
That said, many have found a good soap and water wash, followed by drying on the heat bed at 80c allows PLA to adhere similar to the smooth PEI sheets, and so far they haven't seen any negative effects like rust forming.
RE: Have all powder-coated sheets a PEI layer?
Hi tim-m30,
Thank you for your response. Usually I clean the print surface with iso-propyl alcohol, but I will try the water/soap and 80c drying option. I'll post the result when the printer is free for further experiments :-).
The "type" appears to be more of a production code as my spare smooth PEI has "BH-13" printed on it. What I wasn't expecting was that the powder-coated sheet (0,78mm) was about 0.4 mm thinner as the smooth sheets, (1,16 & 1.19 mm).
Greetings,
Fred Jan
RE: Have all powder-coated sheets a PEI layer?
Hi Fred, the powder coat build plate is a sheet of sprint steel, with a layer of powder coat on each side.
The PEI Stickered build plate is a sprint steel sheet with a layer of adhesive sheet and a layer of PEI on each side
the adhesive and PEI are relatively thick, which is why you have to change Live Z quite a bit when changing from powder coated to stickered sheets
regards Joan.
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
Powder-coated sheets stickyness
Well, I cleaned one half of the powder coat sheet with soap and water, let it dry and even heated it to 80c for 15 minutes. Adjusted the first layer even more and PLA still will not stick properly. Both halves. The (flat test-)objects remain in place during printing, but warp a bit and don't stick at all after bed cooling.
Just for now I think I will just stick to the PEI stickered plate.
Thank you for your responses,
Fred Jan